Freewheel brake hub driven by a motor mounted in the driving wheel



Dec. 30, 1941- G. STEINLEIN arm. 2,267,955

FREEWHEEL BRAKE HUB DRIVEN BY A MOTOR MOUNTED IN THE DRIVING WHEEL FiledFeb. 4, 1959 Inventors PatenteJYDec. 30, 1 941 mbrac IFREEWHEEL "BRAKEnun DRIVEN'YIBY A -'-'MO.TOB MOUNTED 'IN THE Gustav t-steinlein,Mainberg,

and 1' Ludwig "'Bruckmoser,

many

DRIVING near Schweinfurt, Schweinfurt, Ger- Application'February 4,1939, Serial No. 254,568

:In- Germany February 17, 1938 4Claims. (Cl. 180-33) Q The rinvention-ir.elatcs1 :to a free-wheel brake sional stresses oftthemotor; Howeverthis known -construction-does not-allow :a spring action in 'a-directionsubstantially radial ortransverse to v.theaxis-of theihubgdue to thefact that the flanged rings-:whiohareused in connection with the annular.body of rubber prevent transmission of transverse-stresses to saidbody..

Apart from the "torsional vibrations of the motor," there also occurother vibrations originating from 'the fact'thatras yet it has notbeen"v possible-to perfectly "counterbalance the compressive forces ofinertia of the single-cylinder crank drive; that is=to.say, even'withthe best arrangement of 'counterweights intended for thecounterbalancing of the forces caused by the "revolving masses, there:remain 'remnants of forcess-at-the--crankshaft which in form of vibra-:tionszare .transmitted to the frame of the vehicle.

:Polardiagramsof the "forces of inertia of a "single-cylinder -motor.prove that lateral forces of considerable magnitude may manifestthemselves.

.The formerly practised arrangement for the absorption of the'reactingmotor torque by freewheel brakehubs'ofthe kind previouslyalluded to, merely facilitates the cushioning of such forces of inertiaof 'themotor as cause rotatory motion aroundthe hub shaft, while allforces of inertia acting transversely to such 'forces are transmittedto'the chassis in an uncushioned form.

Essentially. =our invention provides the arrangement of the said annularbody of rubber in a mannerenabling itto receive not only theforcesacting'upon it in a tangential direction, and: producing. arotatory. motion around the hub shaft. but also the: forces transverselyoccurring thereto in a substantially radialdirection.

It is by no meansdesirablethat the transverse r substantially'ra'dialmotions'become as big as the tangential ones. That condition can quiteexcel ently be'met by means of an annular body of rubber inxthe'mannerthat the ratio between them tionsinaradial.direction and th se in atangential direction approximates'l to 10.

'Our invention results in the advantage that perfectly cushioned,provided the further condition is also fulfilled according to which themiddle plane of the connecting rod passes through the annular rubberspring. *If with the motor-driven free-wheel brake hub, which in thiscase in addition to the rubber spring requires in form of aball bearinga supporting point for the motorand gear-case respectively against thefree-wheel hub, the middle plane of the connecting rod were not to passthrough'the annular body of rubber, there would still manifestthemselves certain, though minor, remnants of forces which by way ofsuch bearing may pass uncushioned over to the frame.

Our invention further provides the arrangement of the annular body ofrubber on the freewheel brake hub in such a manner as to also providefor a spring action of said annular body of rubber in an axialdirection.I-n this connection it is possible to make the arrangement in such amanner that the abovementioned ball bearing provided as a motor supportis given advanced tension so that by this spring action the annular bodyis permanently kept under some slight axial pressure, and enabled, evenwhen worn. to work free from any play during its entire life.

On its side, the annular body of rubber may be equipped with aprotective covering safeuarding it against destructive influences.Unless the use ol oil-proof synthetic rubber is provided for, it isadvisable to provide for some kind of flexible oil-proof covering, orthe like, especially on the side facing the gear for instance.

In the accompanying drawing there is shown for the purpose ofillustration an axial section of a free-wheel hub with back-pedallingbrake equipped with an elastic annular body of rubber embodying thepresent invention.

In certain aspects the free-wheel hub is similar to that shown in the U.S. Patents 2,138,619, 2,171.810 and 2,179,478, and includes a dishshapeddrum 20, which is keyed to the hub sleeve I for rotation therewith.andwhich has connected to its periphery the spokes (not shown) of thedriving wheel to form a hub for said wheel.

l Occu g forces of the motor crank drive are and. which has areciprocable piston 5 therein.

'dogs 8, rigid with said. bearing cone,

' ing, for instance, of some This casing is yieldably supported at oneend by means of a resilient member II, shown in the form of an annularbody of rubber or similar elastic material forming the sole support forsaid casing at said end. At the other end the casing I2 is supported ona ball bearing I4.

Fixed to the hub sleeve I is a gear 3, driven from the piston 5 througha gear transmission (not shown), which may include a speed changegear,.in the manner shown in the'U. 8. Patent 2,179,478.

A stationary axle 2 to receive the brake this torque to the bicycletorque, and transmits frame I by means of and extending through openingsin the iorlr I and lover 9 in the manner shown and Patent 2,171,810. Inthis manner cone 8 is turning.

To the bearing cone I, or to an intermediate the bearing part It rigidtherewith, there is connected the annular rubber body I I for receivingthe reacting torque of the motor drive. On its outer circumierence theannular body II is rigidly connected by vulcanization to one end of thecasing I2, or to an intermediate part, It rigid with said casing, and atits inner bore periphery it is afllxed. vulcanization. On the to thepart II also by opposite end the casing I2 is supported on the hubsleeve I by means of the ball bearing II.

The annular body II is desirably arranged on the bearing cone I in sucha manner that the ball bearing I4 is held under a certain amount ofadvanced tension. In ther words, the annular body II is so fastened withrespect to the bear ing cone 6 and the bearing ll on the one hand, andwith the casing I: on the other hand, that the outer circumlerentialsection of said annular body is strained held in position and preventedirom inner ring or race li'oi the bearing cone a is attached tothedescribed in U. 8.

towards the right with respect to its inner cir- I cumierential section.This arrangement is eiiected in such a manner as not to impair in any asnot to impede the spring action of the rubber body II. The other innerend of the annular body II facing the gear 3 may also be provided withan appropriate protective covering consistkind of ilexiblecoveringresistant to oil.

Since the annular rubber body II is elastic in a radial directionrelative to the axle 2, the casing I2 supported at one end entirely onsaid body may be moved by vibrations of the motor eccentrically withrespect to said axle. In other words, the casing I2 at this end maytransmit the vibrations of the motor to the elastic body II in adirection transverse to the axis of said casing or body.

The motor cylinder 4 is arranged in such a manner that the plane ofoscillation I8 0! the connecting rod l9 passes through the middle of therubber body II transverse to the axis of said body substantially atright angles thereto as shown in the drawing. In this manner, the compressive forces of inertia are transmitted from the plane in which theyoccur directly to the rubber body II.

The vehicle frame I, the wheel axle 2, the shell I of the tree-wheelbrake hub, the gear 8, the drum ll enclosing the engine. the wheelspokes connected to the periphery of said drum. and the vehicle drivingwheel are firmly interconnected as a unit, so that they rotate inunison, whiletheengine'i, the geargcaslng II, and most parts or thegearing are also interconnected as a unit, and are supported on theshell I by means of the rubber ring II and the ball bearing I4. Thus theengine, casing and other parts described form a unit, which is radially,tangentially and axially movable a limited extent with respect to theother unit. The extent of axial and radial movement of the engine andcasing unit depends on the amount of lost play in the bearing ll. Suchlost play in the bearing I4 is inevitable and its effect is reduced bythe advanced axial tension of the rubber body II as already described.Even assuming that this bearing I4 is tight so "as not to permit anylost play, the engine andcasing unit will tilt or pivot to a limitedextent aboutthe bearing I4, so that this unit will have at the sectionwhere the annular rubber body II is mounted, a limited substantiallyradial movement or a movement transverse to the axis 01 the hub. Theinwardly extending sleeve on the casing 12 embraces the hub sleeve IIloosely'enou'gh so that this limited tilting or pivotal movement of thecasing about the bearing I4 is permitted. In any case there are noparts, such as flanged rings, directly associated with or enclosing therubber body II to prevent the transmission of vibrations to said body ifany occur."

The mobility of the difierent parts in all directlons as describedavoids a transmission 0! the shocks arising from uneven roads, and alsoavoids vibration and resonance of the motor spokes from beingtransmitted to the seat of the rider.-

Due to the arrangement invention, the annular body II does not onlyproduce cushioning in a tangential direction, by which variablemovements of the motor, shocks caused by unevennesses of road surfaces,oscillating mass pressures, and the reacting torque of the motor, arecompensated, but also springing in a radial direction by which,especially in connection with an arrangement under which the plane ofthe compressive middle of the bearing, it receives, and keeps away fromthe vehicle frame the remnant forces of the non-compensated crank drivewhich have as yet not been cushioned by the tangential springing.

Finally, the new arrangement combines with such advantage the additionalone that, due to the installation of a light spring-action operating inan axial direction, there is no play in the counterbearing.

What we claim is:

1. In a free-wheel brake hub of the type driven by a motor mounted on adriving wheel, the combination comprising a stationary member, a casingfor the transmissiongearing of said motor, and an annular body ofresilient rubber fixed to and extending between said casing and saidstationary member, and constituting the sole support for said casingat'the section thereof where said body is mounted, to permit, whileelastically resisting, rotary'and axial vibratory movements of saidcasing, and also vibratory movement of said casing at said section in adirection transverse to the axis of the hub.

in the sense of the forces of inertia (con-- necting rod middle plane)passes through the 2. In combination-a'freewvheel-brake hub, and a motorfor driving'fsaidhubmounted on the driving wheel, said hiib comprising astationary member, a casi'r'rgh'torthe. transmission gearing,

of said motonf'a'nd an annulaiibody of -resilient rubber flxed toand'extendinggbetweensaid cas-' 1 ing and 'said'statlo'narymember,alldfcdnstituting the section v. mql n fl permit," whileelastically resistingi rotar'y and "axial vibratory movementsoifi aidlcasing,- and also vibratory movement of said-'casing-at'said section ina direction transverse to the axis of the hub, said motor being mountedwith the axial plane of its connecting rod in which the compressionforces of inertia manifest themselves, substantially coinciding with theplane passing substantially through the center of the annular body ofrubber in a direction substantially at right angles and transverse tothe axis of said rubber body.

3. In a free-wheel brake hub of the type driven ment of said casing atsaid last-mentioned end in a direction transverse to the axis ofthe'hub,

said rubber body being tensioned axially in normal position of saidbrake hub when said hub is not operated, said tension being transmittedto said bearing through said casing, whereby freeplay" of said bearingis efiected against the resistance of said rubber body.

4. In combination, a free-wheel brake hub,

and a motor for driving said hub mounted on the driving wheel, said hubcompris-inga stationary member, a casing for the transmission gearing ofsaidmotor, and means for supporting said casing, comprising an annularbody of resilient rubber vulcanized to one end of said casing and tosaid stationary member, and a ball bearing device for the other end ofsaid casing,

said annular body constituting the sole support for said casing at oneend to permit, while elastically resisting, vibratory rotary and axialmovements of said casing, and also vibratory movement 01' said casing atsaid last-mentioned end in a direction transverse to the axis of saidhub,

said rubber body being tensioned axially in normal position of saidbrake hub when said hub is not operated, said normal tension beingtransmitted to said bearing through said casing, whereby free play ofsaid bearing is yieldably resisted by said rubber body, said motor beingpo- 'sitioned with the axial plane of its connecting rod in which thecompression forces of inertia manifest themselves substantiallycoinciding with the plane passing substantially through the center ofthe bearing formed by said rubber body in a direction substantially atright angles and transverse to the axis of said rubber body.

GUSTAV STEINLEIN. LUDWIG BRUCKMOSER.

